OFFSET
0,1
EXAMPLE
16 hypercubes surround a single vertex so a(0) = 16.
A 3 X 3 X 3 X 3 hypercube will admit a single hole in its center, so a(1) = 3*3*3*3 - 1 = 80.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Abraham Maxfield, Jun 22 2024
STATUS
approved